In management of deep caries in primary teeth, the partial caries removal approach favored the arrest of dentin carious lesions, reduced cariogenic micro-organisms and the risk of pulp exposure. The carious tissue at the lateral walls of the cavity at the enamel dentin junction (EDJ) was removed by a spoon excavator without carious tissue removal at the pulpal site. After caries removal, restoration using glass ionomer cement (GIC)(GC Fuji IX™GP extra) was completed. Such an approach is called SMART restoration. The serial radiographs of each restoration consisted of three radiographs; immediately after restoration, at the 6-month follow-up and at the 12-month follow-ups. Digital subtraction radiography(DSR) was used to evaluate dentin remineralization following partial caries removal. Image-Pro Plus software was used to evaluate DSR. For evaluating the changes in DSR, areas with increase density show higher radiopacity, whereas areas with decreased density show higher radiolucency. The 6-month and 12-month follow-up radiographs were subtracted from the baseline radiograph.